I’ve been spotting a bunch of jean shirts under heavier outerwear lately. I’ve also seen jean jackets around as a top layer, worn with a big ol’ scarf and rolled up sleeves.
I prefer vintage Levi’s over the newer Forever 21-tailored stuff. Light wash seems to be San Francisco’s preference for winter, with well worn creases and age-softened fabric. The jackets and shirts are worn over shorts, with dresses, or under a blazer.